Recently, ICs have been highly integrated and fast becoming smaller in size. Passive components such as filters for use with ICs have also become smaller in size. Multilayered dielectric passive components employing dielectric substrates are effective in making passive components smaller in size (see, for example, Japanese Laid-Open Patent Publication No. 2002-280805 and Japanese Laid-Open Patent Publication No. 2002-261643).
When a multilayered dielectric passive component is mounted on a wiring board, for example, a wiring pattern disposed on the wiring board and input and output terminals disposed on sides of the multilayered dielectric passive component are electrically connected to each other by soldering or the like (side mounting).
Heretofore, it has also been proposed to use terminals disposed on outer peripheral surfaces of a chip-like electronic component as portions of lower surface electrodes for surface mounting (see, for example, Japanese Laid-Open Patent Publication No. 10-150138).
For mounting a product on a wiring board, the product may be electrically connected by wire bonding or lead wires rather than the side mounting referred to above. Particularly, the side mounting is a main process for mounting passive components.
However, the above side mounting suffers the following problems:
(1) A wide mounting area is necessary. Specifically, a mounting area greater than the area of a mounted surface of the passive component (e.g., a mounting area which is about 1.5 times the mounted surface) is necessary.
(2) Isolation characteristics are degraded by the stray capacitance of electrodes (side electrodes) disposed on side surfaces of the passive component.
(3) Many manufacturing steps are required due to the need for providing side electrodes on side surfaces of the passive component.
(4) Characteristic variations occur because of shield plates installed near the passive component and other adjacent components.
The present invention has been made in view of the above drawbacks. It is an object of the present invention to provide a passive component which will solve the various problems of the side mounting and which is effective in suppressing characteristic variations and simplifying manufacturing steps.